Return-Path: <linux-kernel-owner+w=401wt.eu-S1757888AbXIFPSv@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1757888AbXIFPSv (ORCPT <rfc822;w@1wt.eu>);
	Thu, 6 Sep 2007 11:18:51 -0400
Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756491AbXIFPSm
	(ORCPT <rfc822;linux-kernel-outgoing>);
	Thu, 6 Sep 2007 11:18:42 -0400
Received: from crystal.sipsolutions.net ([195.210.38.204]:35015 "EHLO
	sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1751796AbXIFPSl (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Thu, 6 Sep 2007 11:18:41 -0400
Subject: Re: BUG: scheduling while atomic: ifconfig/0x00000002/4170
From: Johannes Berg <johannes@sipsolutions.net>
To: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Satyam Sharma <satyam@infradead.org>, Florian Lohoff <flo@rfc822.org>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Netdev <netdev@vger.kernel.org>, linux-wireless@vger.kernel.org,
       Michal Piotrowski <michal.k.k.piotrowski@gmail.com>,
       ipw3945-devel@lists.sourceforge.net, yi.zhu@intel.com
In-Reply-To: <20070906082301.GB21929@gondor.apana.org.au>
References: <20070902184439.GA14306@paradigm.rfc822.org>
	 <6bffcb0e0709021659o3856cd06gabc054c949a84397@mail.gmail.com>
	 <alpine.LFD.0.999.0709060923340.26804@enigma.security.iitk.ac.in>
	 <20070906082301.GB21929@gondor.apana.org.au>
Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-P0JM25PSs9MHCk1RoLrB"
Date: Thu, 06 Sep 2007 17:19:55 +0200
Message-Id: <1189091995.28781.99.camel@johannes.berg>
Mime-Version: 1.0
X-Mailer: Evolution 2.10.3 
Sender: linux-kernel-owner@vger.kernel.org
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 1373
Lines: 42


--=-P0JM25PSs9MHCk1RoLrB
Content-Type: text/plain
Content-Transfer-Encoding: quoted-printable

On Thu, 2007-09-06 at 16:23 +0800, Herbert Xu wrote:
> On Thu, Sep 06, 2007 at 10:32:33AM +0530, Satyam Sharma wrote:
> >=20
> > > > [  382.529041]  [<c02c8abc>] dev_close+0x24/0x67
> > > > [  382.529052]  [<e01f402b>] ieee80211_master_stop+0x4a/0x6d [mac80=
211]
>=20
> This is where the bug is.  You cannot call dev_close from an
> atomic context as i33380211_master_stop does it within spin
> locks.

Oh btw. Can we stick a might_sleep() into dev_close() *before* the test
whether the device is up? That way, we'd have seen the bug, but
apparently nobody before Florian ever did a 'ip link set wmaster0 down'
while the other interfaces were still open.

johannes

--=-P0JM25PSs9MHCk1RoLrB
Content-Type: application/pgp-signature; name=signature.asc
Content-Description: This is a digitally signed message part

-----BEGIN PGP SIGNATURE-----
Comment: Johannes Berg (powerbook)

iD8DBQBG4Bqb/ETPhpq3jKURAodYAJ9Ue7BZ2OM/mODT3BxY5BZTViKo5gCgrEkC
LpH1f969DmQIZpNHoSH2Ank=
=vRYa
-----END PGP SIGNATURE-----

--=-P0JM25PSs9MHCk1RoLrB--

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/